import java.util.Arrays;

public class Solution1470 {
    public int[] shuffle(int[] nums, int n) {
        int[] f=new int[nums.length];
        for (int i=0;i<n;i++){
            f[2*i]=nums[i];
            f[2*i+1]=nums[i+n];
        }
        return f;
    }

    public static void main(String[] args) {
        System.out.println(Arrays.toString(new Solution1470().shuffle(new int[]{2, 5, 1, 3, 4, 7}, 3)));
    }
}
